When doctors won't tell . . .
Of all the online nutritional information, nutritional facts, medical and
dietary sites there are to choose from, in an article entitled "How
to ease the pain" The Sunday Times magazine,
Culture, published a list of just five websites it
considered reliable and informative.This site was one of that five.

CONDITIONS
AND DISEASES PREVENTED AND HELPED BY A LOW-CARB, HIGH-FAT DIET

"NH&WL may be the best non-technical book on diet ever
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Does Eating Red Meat Really Increase Colon Cancer?

On Wednesday, 15 June 2005, the British media were full of the latest food scare. A study of nearly half a million people was clear that eating red meat, they said, dramatically increased the chance of getting colon cancer.

But does it? Here is the abstract of that study and a table from it. See for yourself.

Background: Current evidence suggests that high red meat intake is associated with increased colorectal cancer risk. High fish intake may be associated with a decreased risk, but the existing evidence is less convincing.

Methods: We prospectively followed 478 040 men and women from 10 European countries who were free of cancer at enrollment between 1992 and 1998. Information on diet and lifestyle was collected at baseline. After a mean follow-up of 4.8 years, 1329 incident colorectal cancers were documented. We examined the relationship between intakes of red and processed meat, poultry, and fish and colorectal cancer risk using a proportional hazards model adjusted for age, sex, energy (nonfat and fat sources), height, weight, work-related physical activity, smoking status, dietary fiber and folate, and alcohol consumption, stratified by center. A calibration substudy based on 36 994 subjects was used to correct hazard ratios (HRs) and 95% confidence intervals (CIs) for diet measurement errors. All statistical tests were two-sided.

Apart from the processed meats, we have been eating all of these meats for several thousands of years – without any history of colon cancer. Many peoples in the world still do. So why should they be carcinogenic now?

You will notice from the table below that red meat intake does not increase the risk in Aarhus and Potsdam (1.00 means no effect) and it is protective in Italy (0.96 means 4% lower cancer risk in relative terms). In the other countries, there is a slight increase (1.01 means a 1% increase). So in some countries eating red meat seems to be harmful, in another it is beneficial, and in yet more it has no effect one way or the other

You will also notice that the confidence interval figures all cross 1.00, so some of the subjects in all centres used in this trial benefitted from eating red meat even in those countries where it appeared to increase the risk.
So what is going on?

All these countries have different dietary cultures and even people within them eat different foods and combinations of foods. They also will prepare, store and process them in different ways.
As the numbers are all pretty close to 1.00 (which would indicate no effect one way or the other), I suspect that they are merely artifacts which have little if any practical meaning, particularly as lumping fresh meats and processed meats together makes a nonsense of the whole exercise.

And the authors do admit that:

"Our study has several limitations. Most important, methods used in nutritional epidemiology are known to provide imprecise estimates of food intake. Random measurement errors of food intake lead to the attenuation of the disease risk estimates"

So any or all of those could be the answer.

Will I cut down on red meat? No! Although, having said that, I tend not to eat processed foods

And here is one other confounding factor: It has been shown for over a century that lean meat is not as healthy as fat meat. The Italians might have benefitted because they eat a lot more animal fat than do we.

So, the real message might actually be that we should eat fat meat to prevent colon cancer. Just a thought.

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Disclaimer: Second Opinions is the website of Barry Groves PhD, offering online nutritional facts and online nutritional information. This website should be used to support rather than replace medical advice advocated by physicians.sitemap